Invasion of the Atlantic Blob

This year, the east coast of the southern US, the Bahamas, Caribbean and Gulf of Mexico are in for a massive invasion of the Atlantic Blob, aka a 5,000 mile wide mass of sargassum that is creeping westward. It is forecast to hit Florida in July and will be piling up heaps of weed for months after that. For those of us sailing offshore in tropical and subtropical Atlantic waters this year, the weed will be a persistent problem as it can clog salt-water intakes for engines and foul propellers, rudders and daggerboards. Ashore, the weed rots in the sun and makes beach life unpleasant if not unbearable. In the Caribbean this winter, beaches are being cleared by the truckload in an effort to accommodate beach going tourists. The causes of this mighty blob are many and include warming ocean temperatures and the increase of water-borne nutrients in rivers and estuaries that empty into the Atlantic. If there is an upside to the Atlantic Blob it may be that the huge patches of weed provide a rich habitat for a wide spectrum of sea life including the pelagic fish many cruisers love to catch and eat, mahi mahi, wahoo and tuna. So, this year, be wary of sailing through big patches of sargasso weed but if you can’t avoid them, at least you may be able to catch some dinner.